Screw-tap support.



W. H. WICKENZIE. SCREW TAP SUPPORT. APPLlcATloN FILED JUNE 4. 191g.

Patented Feb. 4:, 191).

2 SHEETSMSHEET l.

- MAM/am W. H. MCKENZIE.

SCREW TAP SUPPORT.

APPucATioN f1LEn1uNE4.19ea

Patented Feb. 4, 19H).

2 SHEETS-SHEET 2 WILLIAM H. MCKENZIE, OF OAKLAND, CALIFORNIA.

'SCREW-Tar sweeter.V

Specification of Letters Patent.

Patented Feb. 4, 1919.

Application led June 4, 1918. Serial No. 238,161.

To all whom t mag/'concern Be it known that-LWNILLIMM H. MCKEN- zr, a citizen of the United States, residing at Oakland, in the county of Alameda and 10 conforms to and i's 'trating the mannerA State of California, have invented certain' Screw-Tap neu7 and useful Improvements in Supports, of which the following is a .specification. v

This invention relates` to implements for guiding a screw tap when cutting a screw thread in an opening, and has for one of its objects to provide a simply constructed device which may be-readily applied without structural change eitherin the tap 0r in the body in which the' thread is to be cut, and which may be readily adapted to bodies of various forms and sizes.|`-

lVith these and other objects in view, the invention consists in certain novel features of construction, as hereinafter shown and described and thenspeciically pointed out inthe claim; and in the drawings illustrative of the preferred embodiment of the invention AFigure 1 is a sectional elevation of the improved implement,

Fig. 2 is a plan View of .the paltsv Shown in Fig. 1,

Fig. 3 is a view similar to Fig. 1. illus of applying the improved device to a body having a curved surface.

The improved device comprises a sup-l porting member represented as a Whole at 10 and provided with' a threaded aperture 11 therethrough. The lower face of the bod) adapted to bear upon the Work in which the thread is to be cut. For instance in Figs. 1 and 2 the member in which the thread is to be cut, indicated at 12, is provided with a fiat face, and the member 1.0 will be provided with a correspondingly flat lower face. In Fig. 3. the member in which the thread is to be cut, indicated at 13. is circularA or with a curved surface. and the body 10 is vformed with a reversely inclined lower face 14 to engage the curved face of the member 13 as shown.

. The aperture to be threaded is indicated at 15, and the thread cutting tap at 16. Fittingnwithin the aperture 11 is a guide sleeve 171' eternally threaded as shown at 18 to adjus'eably engage the threads of the aperture 1l, and internally threaded to receive the mutilated threads 19 of the tap. By this means the tap is efiectually guided within the aperture 15 of the member 12 and accuvracy of the operation of the `tapV assured.

By the use of the improved device it is practically impossible to tap a hole in the member 10 other thanfperfectly straight, or at right angles to the outer surface of the work. 'By means of the improved device any person without previousskill or'knoivledge can thread an aperture in a plate or other work with accuracy and precision. The body l0 is maintained at all times in parallel relation to the surfaceI of the. member to be tapped. and no pressure upon'the tapping tool other than that provided by the guiding device itself. is necessary to produce maximum results.

The use of the improved device obviates danger of breaking or injuring the tapping tool. By using the improved device no necessity exists for squaring up the work with a hand square. 'which must be done under ordinary circumstances, and the necessity `for employing supporting brackets,

jigs, drill presses andlikeedevices is obviated vertically with respect to the supporting member.

ln testimony whereoffl aihx my signature. WlLulAM-H. MoKEZTE. [Le] furnished to the trade as a new 

